KR20080087858A - Efficient reporting of information in a wireless communication system - Google Patents

Abstract

Techniques for efficiently sending reports in a wireless communication system are described. Reports may be sent repetitively in accordance with a reporting format. A terminal receives an assignment of a control channel used to send reports and determines a reporting format to use based on the assignment. The reporting format indicates a specific sequence of reports sent in specific locations of a control channel frame. The terminal generates a set of reports for each reporting interval and arranges the set of reports in accordance with the reporting format. The terminal repetitively sends a plurality of sets of reports in a plurality of reporting intervals. Reports may also be sent adaptively based on operating conditions. An appropriate reporting format may be selected based on the operating conditions of the terminal, which may be characterized by environment (e.g., mobility), capabilities, QoS, and/or other factors.

Description

EFFICIENT REPORTING OF INFORMATION IN A WIRELESS COMMUNICATION SYSTEM}

The present disclosure generally relates to communication, and more particularly to techniques for reporting information in wireless communication systems.

The wireless multiple access communication system can simultaneously support communication for a plurality of terminals on the downlink and uplink. The downlink (or forward link) refers to the communication link from the base station to the terminal, and the uplink (or reverse link) refers to the communication link from the terminal to the base stations.

The terminal may be located system-wide and may observe different channel conditions. In addition, these terminals may have different data requests and / or capabilities. In order to obtain proper service from the system and to ensure proper system operation, the terminal may report various types of information. For example, the terminal may estimate the channel quality of the downlink for the base station and may send a channel quality report to the base station on the uplink. The base station may use the channel quality report to allocate radio resources to the terminal and / or to select a sufficient data rate for transmission to the terminal on the downlink.

Although appropriate or important, the information reported by the terminal is expressed as overhead in the system. Therefore, it is desirable to transmit information as efficiently as possible so that more available radio resources can be used to transmit data. Therefore, there is a need for a technique for efficiently reporting information within a wireless communication system.

summary

Techniques for efficiently sending reports in a wireless communication system are described herein. Reports may carry various types of information, such as channel quality, requests for radio resources, available transmission power, interference, backlog information, sector information, and the like.

In one embodiment, the reports are sent repeatedly according to the reporting format. The terminal receives the assignment of the control channel used to send the reports and determines the reporting format that can be used based on the assignment. For example, one reporting format may be used for full (eg, full tone) allocation of control channels, and another reporting format may be used for partial (eg, split tone) allocation. The reporting format represents a particular sequence of reports sent to a specific location of a control channel frame. The reporting format may have a different appearance as described below. The terminal generates a set of reports for each reporting period and sorts the set of reports according to the reporting format. The terminal repeatedly transmits the plurality of sets of reports in the plurality of reporting intervals using the reporting format.

In yet another embodiment, the reports are suitably sent based on the operating conditions. The terminal sends reports to the base station according to the first reporting format. The first reporting format may be a default reporting format or may be selected based on a current operating condition of the terminal. The operating conditions may be characterized by the environment of the terminal (eg, mobility), the performance of the terminal, the quality of service (QoS) of the traffic for the terminal, and the like. Changes in operating conditions are detected. The second reporting format is then selected based on the sensed change in the operating condition. The terminal then sends the reports according to the second reporting format. The appropriate reporting format may be selected for use whenever a change in operating conditions is detected.

Various aspects and embodiments of the invention are described in more detail below.

Aspects of embodiments of the invention will become more apparent from the following detailed description when taken in conjunction with the drawings, in which reference numerals identify corresponding references throughout the specification.

1 illustrates a wireless communication system.

2 illustrates an example signal structure.

3 shows an exemplary structure of a dedicated control channel (DCCH).

4 illustrates an example allocation of DCCH.

5 shows a report transmission scheme for a DCCH.

6 shows a reporting format for full-tone allocation of DCCH.

7 shows another reporting format for full tone allocation.

8 shows a reporting format for a three-way split tone,

9 shows a report transmission scheme for a control channel.

10 illustrates a reporting transmission scheme with a selectable reporting format.

11 shows a process for repeatedly sending reports.

12 illustrates an apparatus for sending reports repeatedly.

13 shows a process for sending reports based on an operating condition.

14 shows an apparatus for sending reports based on an operating condition.

15 shows a block diagram of a base station and a terminal.

The term "exemplary" is used herein to mean "provided as an example, illustration, or illustration." Any embodiment or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

1 shows a wireless communication system 100 having a plurality of base stations 110 and a plurality of terminals 120. A base station is a station that communicates with terminals. A base station may include and may be called any or all of the functions of an access point, a Node B and / or any other network entity. Each base station 110 provides communication coverage for a particular regional area 102. The term "cell" may be considered a base station and / or its coverage area depending on the context in which the term is used. In order to improve system capacity, the base station coverage area may be divided into a plurality of small areas, for example three small areas 104a, 104b and 104c. Each small area may be served by a respective base station sector (BSS), which may also be referred to as a base transceiver subsystem (BTS). The term "sector" may be called a BSS and / or its coverage area depending on the contact in which the term is used. For a sectorized cell, the BSSs for all sectors of that cell are generally co-located within the base station for the cell. The reporting technique described herein may be used for systems with unsectored cells as well as systems with sectorized cells. In the description below, the term “base station” generally refers to a base station serving a sector as well as a base station serving a cell.

For the centralized technique, system controller 130 is coupled to base stations 110, provides coordination, and controls for these base stations. System controller 130 may be one network entity or a collection of network entities. For distributed technology, a base station may communicate with other base stations when needed.

Terminals 120 may be distributed throughout the system, and each terminal may be fixed or mobile. The terminal may include and may be called any or all functionality of a wireless terminal (WT), access terminal (AT), mobile station (MS), user equipment (UE), subscriber station and / or any other entity. The terminal may be a wireless device, cellular telephone, PDA, wireless modem, portable modem, or the like. The terminal may communicate with one or more base stations via transmissions on the downlink and uplink. In the description below, the terms "terminal" and "user" are used interchangeably.

The reporting techniques described herein may be used for various communication systems. These techniques include various wireless technologies, and code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), quadrature FDMA (OFDMA), flash-OFDM®, and single-carrier FDMA. It may also be used for multiple access systems such as (SC-FDMA). The OFDMA and SC-FDMA frequency bands (e.g., system bandwidth) are divided into multiple quadrature tones, also called subcarriers, subbands, bins, and the like. Each tone may be modulated with data. In general, modulation symbols are sent in the frequency domain with OFDMA and in the time domain with SC-FDMA. The techniques may also be used for wireless communication systems that utilize a combination of multiple access schemes, such as, for example, OFDMA and CDMA.

For clarity, certain aspects of the reporting technique are described below for an exemplary OFDMA system. In general, an OFDMA system may utilize any tone structure with any number of total tones and any number of tones available. In an exemplary embodiment, the OFDMA system utilizes a tone structure with 128 total tones and 113 usable tones. An OFDM symbol may be generated by known techniques and may be transmitted during an OFDM symbol period (or simply a symbol period).

The reporting techniques described herein may be used with various signal structures. The signal structure represents how data and signals are transmitted. For clarity, an example signal structure is described below.

2 illustrates an embodiment of a signal structure 200. The timeline for transmission is divided into superultra slots. Each superultraslot has a predetermined time period (eg, about 13.1 seconds) and includes eight ultraslots with indices from 0 to 7. Each ultraslot contains 18 beaconslots with indices from 0 to 17, and each beaconslot contains eight superslots with indices from 0 to 7. For the downlink, each superslot includes a header H followed by eight slots with indices from 0 to 7. The superslot header is two symbol period ranges, each slot is 14 symbol period ranges, and each superslot is 114 symbol period ranges. For the uplink, each superslot includes an uplink access channel (UL.ACH) followed by 15 dwells with indices from 0 to 14. The UL.ACH is nine symbol period ranges, each dwell is seven symbol period ranges, and each superslot is 114 symbol period ranges.

2 shows a specific signal structure. Various other signal structures may also be used, which are within the scope of the present invention. For clarity, the reporting structure is described below for the signal structure shown in FIG.

In one embodiment, the terminal is segments of an assigned dedicated control channel (DCCH) that transitions to an ON state with respect to the base station. A connection may be thought of as a set of established channels between a base station and a terminal for physical (PHY) and / or Medium Access Control (MAC) layers. While on, the terminal may receive data on the downlink and / or transmit data on the uplink. The terminal uses the allocated DCCH segments to send reports to the base station on the uplink. These reports may be various types of information as described below.

DCCH may be implemented in various ways. In one embodiment, the DCCH includes a set of logic tones, also called DCCH tones (eg, 31 logic tones). Each DCCH tone may be mapped to a specific usable / physical tone in each dwell, and may hop from physical tone in different dwells to physical tone based on tone hopping operation.

3 illustrates an embodiment of a DCCH structure 300. In this embodiment, 40 DCCH segments with indices from 0 to 39 are defined for each DCCH tone within each beaconslot. The beaconslot contains 64 slots, or 128 halfslots with indexes from 0 to 127 evenly. Each DCCH segment uses one tone and spans three halfslots. The five DCCH segments consist of the last 15 of each superslot with the first halfslot where the first halfslot is used for UL > ACH. Therefore, DCCH segments 0 through 4 consist of half slots 1 through 15 in superslot 0, DCCH segments 5 through 9 consist of half slots 17 through 31 in superslot 1 ( 3, DCCH segments from 35 to 39 consist of half slots from 113 to 127 in super slot 7.

In the embodiment shown in FIG. 3, 31 logic tones are used for the DCCH, 40 DCCH segments are defined for each DCCH tones in each beaconslot, and a total of 1240 DCCH segments are available in each beaconslot. The available DCCH segments may be allocated to the terminal in various ways.

4 illustrates an example allocation scheme for the DCCH structure in FIG. 3. In one embodiment, each DCCH tone may be assigned to one or a plurality of users. Multiple DCCH modes may be defined. Each DCCH mode may correspond to a certain number of users to which given DCCH tones are assigned. In full DCCH mode, also called full-tone format / assignment, a DCCH tone is assigned to a user who may send a report to all DCCH segments of those tones. In 1/2 DCCH mode, also called two-way split tone format / allocation, DCCH tones are assigned to two users. In 1/3 DCCH mode, also called three-way split tone, the DCCH tone is assigned to three users. In 1/4 DCCH mode, also called 4-way split tone, the DCCH tone is assigned to four users. Other DCCH modes may also be defined. For N-way split tone allocation where N> 1, N users may send reports in a time division multiplexed (TDM) method on a DCCH segment of one DCCH tone. DCCH segments may be assigned to these users by iterating through N users and assigning one DCCH segment to each user in each cycle. As shown in FIG. 4, each user then becomes uniformly distributed allocated DCCH segments. For each all assignment, each user may send reports in the DCCH segments assigned to that user.

3 and 4 illustrate certain embodiments of the allocation scheme and structure for the DCCH. These embodiments provide a frequency change through frequency hopping and a time change through the allocation of widely distributed DCCH segments in time. DCCH may be implemented in other ways, or may be partitioned and allocated to users in other ways. For example, the DCCH may be implemented with certain tones in certain symbol periods. As another example, users may be assigned multiple DCCH segments within a given time period. For clarity, much of the description below is for the embodiment shown in FIGS. 3 and 4.

5 shows an embodiment of a report transmission scheme 500 for a DCCH. In this embodiment, the terminal sends a set of reports on the DCCH within each reporting period of one beacon slot to the base station. Each set of reports is sent using a reporting format that is known apriori or can be assured by both the terminal and base station.

In general, a reporting format is a structure for one or more reports. The reporting format may carry various parameters such as what type of report is sent, how often each type of report is sent, the location and length of each report, and / or other information. The reporting format may also be called a reporting structure, a control channel format, a DCCH format, or the like. Reports may be sent efficiently because overhead information (eg, headers) is not generally needed to convey the reporting type, location, size using the reporting format. All or most of the overhead information is implied from the reporting format. Therefore, reports may contain all or most useful information and very little overhead information.

As shown in FIG. 5, reports may be sent periodically using the same reporting format for each reporting period, which is one beaconslot of FIG. 5. The same set of reports is then sent to each reporting interval. However, values in reports may vary from one report set to another based on conditions and / or measurement results in different reporting intervals. The interpretation of the reports in each set remains fixed and determined by the reporting format.

The terminal may send various types of reports. Table 1 lists arbitrary report types and briefly describes each report type.

                              Table 1

Report type DL SNR UL request Delay information DCCH backoff Beacon ratio Magnetic noise SNR Sector boundary

DL SNR represents the received SNR or downlink channel quality observed at the terminal for the base station. The terminal may receive transmissions from one or more base stations on the downlink. The terminal may measure the DL SNR of each base station based on the downlink pilot channel (DL.PICH) transmitted by the base station. The terminal may generate full and delta DL SNR reports for each base station. The full DL SNR report gives the DL SNR measured in the current reporting interval. The delta DL SNR report gives a delta SNR that is the difference between the DL SNR in the current reporting period and the DL SNR in the previous reporting period. Delta SNRs may also be called relative SNRs or distinct SNRs. If the terminal can receive downlink transmissions from multiple base stations, the full DL SNR report for the base station may also indicate whether the base station is preferred.

The magnetic noise SNR is the saturation level of the DL SNR and is the SNR that the receiver at the terminal observes the received signal when the base station transmits the signal with infinite power. The saturation level of the DL SNR is determined by the magnetic noise of the terminal receiver, which may be caused by channel estimation error and / or other factors. The terminal may determine the saturation level of the DL SNR as described below. The terminal may assume that the DL SNR may be given as follows when the base station transmits at power P;

식(1)

Formula (1)

G represents the pass gain of the radio channel from the base station to the terminal. The amount of equation (1) is given in linear units.

The term G • P refers to the received signal power at the terminal. The term N represents the received interference power. The term a ₀ · G • P denotes magnetic noise, and a higher value of a ₀ denotes a higher value of magnetic noise. The terminal may measure the received power of the downlink null channel (DL.NCH) to determine the interference power N. The terminal uses DL.PICH (SNR ₀ It is also possible to measure the SNR (represented by) and the received power (represented by G.P ₀ ). The saturation level of the DL SNR is equal to 1 / a ₀ and may be calculated as follows:

식 (2)

Formula (2)

The quantities in equation (2) are given in linear units.

The UL request carries backlog information at the terminal. The terminal may maintain one or more (eg, up to four) MAC frame queues. Each MAC frame queue may buffer MAC frames for one request group. MAC frames may be generated from packets of a higher layer protocol. Each packet may be mapped to one request groups, and all MAC frames generated for that packet may be located in associated MAC frame queues. The UL request may indicate the backlog information for the terminal and carry the number of MAC frames in the (eg four) request groups that the terminal may transmit. The base station may assign traffic channel segments (or radio resources) to the terminal based on other factors such as backlog information, channel conditions and / or priority of data to be transmitted by the terminal.

The delay information carries the amount of delay experienced by the data to be transmitted by the terminal. The terminal may track the delay experienced by MAC frames in each group request. For example, the terminal may maintain D [k] indicating the head of line of the current line experienced by the oldest MAC frames in request group k, where k = 0, .., 3. . The delay information may then include the D [k] or delay of the MAC frames in the request group. The base station may allow to consider the delay information in allocating traffic channel segments to the terminal.

DCCH backoff carries the amount of transmit power available at the terminal for data transmission on the uplink. The terminal may adjust the transmit power of the DCCH to obtain a target level of performance for reports sent on the DCCH. The terminal has a specific maximum transmit power that may depend on the design of the terminal. DCCH backoff is the difference between the maximum transmit power and the DCCH transmit power, and may be given as:

식(3)

Formula (3)

wtULDCCHTxPower is the transmit power of UL.DCCH per tone, wtPowerMax is the maximum transmit power of the terminal, and wtULDCCHBackOff is the DCCH backoff.

All quantities in equation (3) are given in units of dBm. DCCH backoff may be used to assign the appropriate number of tones of tones and / or may be used to select an appropriate data rate for transmission on the uplink.

The beacon ratio carries the interference potentially caused by the terminal to different base stations and may be used for interference management on the uplink. The terminal may measure the neighbor base station channel gain (or signal strength) related to the channel gain of the serving base station. The terminal may measure the received power (PB ₀ ) of the beacon of the serving base station, or may measure the received power (PP ₀ ) of the pilot channel. The terminal may similarly measures the received power (PP _i) of the received power (PB _i) and a pilot channel of the beacon of each neighbor base station i. The terminal can then calculate the channel gain ratio G _i for each base station i as follows:

식 (4)

Formula (4)

K is the transmission power per tone of the beacon to the transmission power of the pilot channel, and Z ₀ is a scaling factor that depends on how the tones are used at the serving base station.

A typical beacon ratio report (BNR) may be generated based on the channel gain ratio of neighboring base stations as follows:

또는 식(5)

Or equation (5)

식(6)

Formula (6)

b ₀ is an uplink loading factor broadcast by the serving base station and b _i is an uplink loading factor broadcast by the neighboring base station i.

The quantities in equations (5) and (6) are given in linear units. The uplink loading factor b _i represents the loading on the uplink observed by base station i for all terminals served by base station i. The uplink loading factor is used to indicate the amount of traffic load seen by base station i. Base stations may exchange or broadcast their loading factors to control uplink interference and increase overall throughput.

The terminal may calculate general beacon ratio reports using equation (5) in beaconslots with even indices and equation (6) in beaconslots with odd indices. If the terminal is sent to a serving base station, the general beacon ratio reports provide the cost of interference to all neighbor base stations (with equation (5)) or the nearest neighbor base station (with equation (6)).

A special beacon ratio report may be generated for neighbor base station k as follows.

식(7)

Formula (7)

The special beacon ratio provides the cost of interference to a particular base station k, if transmitted to the base station the terminal is serving.

The sector boundary carries information about whether the terminal is located at the boundary of two neighboring sectors of the same base station and if so, which sector boundary. Sector boundary information may be used by the base station to coordinate the scheduling of traffic channels in two sectors to provide better service to the terminal when the terminal is located at the sector boundary. For example, the base station may reduce the transmit power in one sector so that the terminal experiences less interference from that sector.

Table 1 lists some types of reports that may be sent by the terminal to support efficient data transmission and proper system operation. Less, different and / or additional types of reports may also be sent, which are within the scope of the present invention.

6 illustrates an embodiment of a reporting format 600 that may be used by a terminal having full tone allocation for a DCCH. The reporting format 600 may cover a DCCH frame of 40 DCCH segments and be transmitted in eight superslots of one beaconslot. A DCCH frame is a unit of DCCH that is used to send a set of reports in accordance with the reporting format. The reporting format 600 has six information bits in each DCCH segment. The reports sent in each DCCH segment of the reporting format 600 are shown in FIG. 6. In particular, 5-bit DL SNR report and 1-bit UL request are sent in DCCH segment 0, 2-bit mode indication and 4-bit report are sent in DCCH segment 1, 3-bit delta DL SNR report and 3-bit UL request are sent in DCCH segment 2, and so on.

Table 2 lists the different types of reports and the number of reports of each type included in the reporting format 600. For reporting format 600, field D may be configured to send a report of one of four possible types that appear in field C. Configurable field D provides the flexibility of sending reports at any overhead cost for field C.

                          Table 2

7 illustrates an embodiment of a reporting format 700 that may be used by a terminal having full tone allocation for a DCCH. The reporting format 700 covers a DCCH frame of 40 DCCH segments and has six information bits in each DCCH segment. The reports sent in each DCCH segment of the reporting format 700 are shown in FIG. 7. The reporting format 700 may be used on more slowly changing channels. Therefore, full DL SNR reports and delta DL SNR reports are sent less frequently in reporting format 700 than in reporting format 600, as shown in the last two columns of Table 2. The bit saved by sending fewer DL SNR reports is used for more configurable field D.

8 illustrates an embodiment of a reporting format 800 that may be used by a terminal having a three-way splinter tone for DCCH. The reporting format 800 covers a DCCH frame of 40 DCCH segments and has 8 information bits in each DCCH segment. However, only 13 DCCH segments are allocated to the terminal, 26 different DCCH segments are allocated to the other terminal, and the last DCCH segments are reserved (Rsvd). Each assigned DCCH segment reports of the reporting format 800 are shown in FIG. 8. Since very few DCCH segments are available for reporting format 800, reports are generally sent at a low frequency rate.

In one embodiment, the terminal sends reports, in accordance with the reporting format, in each reporting interval upon receiving the assignment of the DCCH. In another embodiment, the terminal sends reports of a special set of reports in the first superslot after receiving the DCCH segment, and then sends the reports using the reporting format. The special set of reports may include, for example, a 4-bit UL request, a 5-bit DL SNR report, a magnetic noise SNR report, a beacon ratio report, a DCCH backoff report, and the like. Therefore, the terminal may quickly provide all the important information in the special set of reports to the base station.

In the embodiment shown in FIGS. 6 and 7, six information bits may be sent in each DCCH segment. In the embodiment shown in FIG. 8, eight information bits may be sent in each DCCH segment. Each DCCH segment may contain a fixed number of tone symbols, for example 21 tone symbols. A tone symbol is one tone within one symbol period and may be used to transmit one modulation symbol. For a given number of tone symbols, more information bits may be transmitted using modulation schemes and coding with less redundancy, resulting in lower reliability.

6-8 illustrate a particular embodiment of three reporting formats, each having a particular sequence of reports arranged in a particular order. Various other reporting formats may also be defined.

In one embodiment, different reporting formats are defined for different operating conditions for a given DCCH allocation (eg, full tone allocation or three-way split tone allocation). The operating conditions of the terminal may be characterized by various factors such as the environment of the terminal, the performance of the terminal, the QoS of the traffic transmitted by the terminal, how the system operates, and the like. These parameters determine what type of report will be sent. It can also affect how often you send each type of report and what information is included in each report.

The environment of the terminal may be characterized by various factors such as the terminal's mobility (eg, low or high mobility), channel conditions (eg, low or high SNR), and the like. The reporting format for low mobility (eg, fixed or low speed) may send SNR reports with less frequency than the reporting format for high mobility (eg, high speed). The SNR report for low mobility channel conditions may have more bits than the SNR report for high mobility channel conditions. The reason is that SNR in high mobility channel conditions tends to change. Given the loop latency associated with SNR measurement and reporting, it may not be necessary to report SNR very accurately. Since the base station can reliably receive reports with less coding surplus, a reporting format with more bits and / or more bits for certain reports may be used for good channel conditions.

The performance of the terminal may indicate whether the terminal supports one or multiple frequency channels (or tone blocks). Performance includes multiple input multiple output (MIMO), single input single output (SISO), single input multiple, which may have different reporting needs. It may also indicate whether the terminal supports a single-input multiple-output (SIMO), multiple-input single-output (MISO) operation. One data stream may be sent on one spatial channel with SISO, SIMO, and MISO. Multiple data streams may be transmitted simultaneously on multiple spatial channels with MIMO. The reporting format for SISO, SIMO and MISO may carry one SNR value for one spatial channel in the SNR report. The reporting format for MIMO may send any number of SNR reports each having multiple SNR values for multiple spatial channels in one SNR report or one SNR value for one spatial channel.

QoS of the traffic may affect the reporting. Different types of traffic (eg, voice, video, packet data, etc.) may have different QoS. QoS may be quantified by delay endurance, peak data rate, average data rate, delivery options, and / or other criteria. For example, because of the time sensitive nature of voices, voices may be associated with maximum delivery, short delay requests, and fixed data rates. Packet data may be associated with longer delay requests, high peak data rates, and guaranteed delivery. The reporting format may include more UL requests and / or UL requests with more details when there are different QoS traffic.

How the system works can also affect reporting. For example, the system may use time division duplexing (TDD) or frequency division duplexing (FDD). Within a TDD system, it may be assumed that the downlink and uplink share the same frequency band, and the downlink channel is equivalent to the uplink channel. In this case, the base station may estimate downlink channel conditions (eg, DL channel gain and / or SNR) based on uplink transmission (eg, pilot) from the terminal. In an FDD system, the downlink and uplink use different frequency bands, and the downlink channel may not be correlated with the uplink channel. In this case, the terminal may estimate downlink channel conditions and send reports to the base station. Different reporting formats may be used for TDD and FDD systems.

In general, the reporting format may include any combination of report types, any number of reports of each type, and any sort of reports. The number of reports of each type depends on the capacity of the control channel assignment used to send the report, the importance or threshold of that report type in relation to other report types, and how quickly the information of the report types (which may be environment dependent) is available. It may be selected based on changes and / or other factors. Each report may be of any size and may have any format / structure. The reports may be sorted so that, for example, in one DCCH segment as shown in FIGS. 6-8, each report is transmitted completely in one transmission, which may improve the use of these reports. Reports may be sent in multiple transmissions, for example in multiple DCCH segments. The reporting format may include a combination of fixed and configurable fields as shown, for example, in FIGS. 6-8. The reporting format may also include only fixed fields or only configurable fields.

In general, any number of reporting formats may be defined for a given control channel assignment. Each reporting format may be designed for specific operating conditions. In one embodiment, different reporting formats may include different reports that are more appropriate for different operating conditions covered by these reporting formats. In yet another embodiment, different reporting formats may have the same set of reports that may be sorted in different orders and / or with different formats / structures. Bit splitting between different reports may be different for different reporting formats. For example, if the DCCH segment has a fixed number of information bits, the UL request may drop from 4 bits to 3 bits so another report may get additional bits. Regardless of how the reporting format is defined, an appropriate reporting format may be selected for use based on the current operating conditions of the terminal.

9 illustrates an embodiment of a report transmission scheme 900 for a control channel, eg, a DCCH. In one embodiment, a set of reports are sent on the control channel in each reporting period, which may be any time period. Each set of reports is sent using a reporting format 910 within one control channel frame. In this embodiment, the reporting format 910 includes L reports sent during the M time period, typically L > 1 and M > The time period may be any time period or may be a range of one or more symbol periods. The time period may correspond to any other time period, or three half slots shown in FIG. 3. The M time periods may have the same or different periods. Any number of information bits may be sent in each time period. The reporting format 910 may include any type of report and any number of reports of each type. Each report may have any size and may transmit one or more time periods. As shown in FIG. 9, the reporting format 910 is used repeatedly in each reporting interval. Therefore, report x with x = 1, ..., L is transmitted at the same location of the control channel of each reporting interval.

10 illustrates an embodiment of a report transmission scheme 1000 for a control channel having a selectable reporting format. First, at time T ₁ , operating conditions of the terminal are determined. The appropriate reporting format A for the current operating condition is selected for use. The set of reports is sent in each reporting interval using reporting format A. At time T ₂ , a change in operating conditions is sensed. A more appropriate reporting format B for the new operating condition is selected for use. Thereafter, the set of reports is sent in each reporting interval using reporting format B. At time T ₃ , a change in operating conditions is detected again. The more appropriate reporting format C for the new operating condition is selected for use. Thereafter, the set of reports is sent in each reporting interval using reporting format C.

Switching in the reporting format may be obtained in various ways. In one embodiment shown in FIG. 10, the reporting format includes a reporting format type field that identifies the reporting format. A set of reporting formats may be supported. The definition of each reporting format in the set may be known a priori by the base station and the terminal, such as carried during a call setup or via a signal at a switching time, transmitted via a broadcast message. The appropriate reporting format may be dynamically selected in each reporting period and may be identified by the reporting format type field. In yet another embodiment, the reporting format includes a field indicating the reporting format for use in subsequent reporting intervals. In another embodiment, the change in reporting format is obtained using signal messages between the base station and the terminal, for example via a different traffic channel than the DCCH, using control messages.

In one embodiment, the terminal may automatically select the reporting format. The terminal may determine its operating conditions (e.g., environment, performance, etc.) or may select an appropriate reporting format based on the operating conditions. In another embodiment, the terminal and the base station may together select a reporting format. For example, the terminal may determine its operating conditions, propose a reporting format, and the base station may accept or reject the proposed reporting format. In yet another embodiment, the base station may select a reporting format for the terminal, for example based on information provided by the terminal.

The terminal may use one reporting format until a new reporting format is selected, for example by a sensed change in operating conditions. The terminal may also use multiple reporting formats in some way. For example, the terminal may select between two reporting formats A and B. The reporting format A may be used in even reporting intervals or the reporting format B in odd reporting intervals. The reporting format 600 in FIG. 6 includes four small reporting formats—a first reporting format for superslots 0, 2, 4, and 6, a second reporting format for superslots 1 and 5, and superslot 3. It may be regarded as consisting of a third reporting format for and a fourth reporting format for Superslot 7.

The terminal may have multiple connections with multiple base stations. The terminal may use the same reporting format for all base stations or may use a different reporting format for different base stations.

Each report may have any format / structure appropriate for that report. The report may carry one value or multiple values. In one embodiment, one or more lookup tables may be defined for each type of reports. Each lookup table may map a calculated value to a report value having a certain number of bits. As an example, for DL SNR, one lookup table may map the calculated DL SNR value for the base station to a full DL SNR report of 5-bit values for non DL macrorodiversity, and Another lookup table may, for DL macrodiversity, map the calculated DL SNR value to a full DL SNR report of 5-bit values, as well as whether the base station is preferred, and another lookup table maps the delta DL SNR value to 3 bits. The value may be mapped to a delta DL SNR report. Each lookup table may be defined to obtain good performance for the corresponding report. Table 3 shows an example lookup table in which DL SNR values in the range between -13 dB and +29 dB map to a full DL SNR report of 5-bit values. Table 3 shows an example lookup table in which delta DL SNR values in the range between -5 dB and +5 dB map to a delta DL SNR report of 3-bit values. Another lookup table may be defined for other types of reports.

                                Table 3

In one embodiment, one dictionary is used for each report type. The dictionary for a report type defines a specific format / structure for each report of that type. The dictionary defines how each report is interpreted. For example, the dictionary for DL SNR may have one format for the 5-bit DL SNR report for non-DL macrodiversity, and another format for the 5-bit DL SNR report for DL macrodiversity. It may have another format for the 3 bit DL SNR report. The same dictionary and thus the same three SNR report formats may be used for all reporting formats with DL SNR reports.

In another embodiment, multiple dictionaries are used for a given report type. Each dictionary carries a specific format / structure for each report of that type. Multiple SNR dictionaries may be used for SNR reports. For example, an SNR report with low mobility may use a different format than an SNR report with high mobility. Different lookup tables may use SNR reports for low and high mobility. As another example, the SNR report for good channel conditions may use a different format than the SNR reports for bad channel conditions. The range of SNR values and / or the SNR step size may be different for different SNR report formats. Multiple request dictionaries may be used for UL requests, eg, different QoS. Each request dictionary may use a different format for the UL request and / or provide specific backlog information (eg, number of MAC frames and / or delay information) at the terminal. For example, a 4 bit UL request may have different meanings in different request dictionaries. Multiple dictionaries may be used for other types of reports.

Returning to FIG. 9, a report may carry a value that is within the range of values for that report. Report values may have different meanings in different dictionaries. Therefore, the information carried in the report (ie the actual meaning of the report value) is determined by both the dictionary and the report value used for the report.

The specific dictionaries used for each report may be conveyed, either explicitly or implicitly. In one embodiment, each reporting format uses a specific dictionary for each report. In one embodiment, the dictionary for each report type is implicitly carried by the reporting format. For each reporting selected for use, the terminal and base station know a priori the specific dictionary to use for DL SNR reports, the specific dictionary to use for UL request, and the like. Both the terminal and the base station can properly interpret each report transmitted using the selected reporting format.

In yet another embodiment, the dictionary may be selected for each report type regardless of the reporting format. For example, multiple request dictionaries may be available for a given reporting format. Different dictionaries may be selected for use in different operating scenarios (eg, different mobility). The appropriate dictionary may, for example, select whether or not whenever a change in operating conditions is detected, regardless of or in conjunction with the selection of the reporting format. The selected dictionary may be conveyed via a signal or in some other way.

The information bits for the reports may be encoded, modulated and processed in various ways. In one embodiment, the information bits transmitted in the DCCH segment are encoded (eg, with a block code) to generate code bits. The code bit is then mapped to modulation symbols based on the modulation scheme. The modulation symbols are sent in tone symbols for the DCCH segment. In one embodiment, the sequence of scrambling bits is used to scramble code bits or information bits in all or certain DCCH segments. For example, the scrambling sequence may be applied to some reports and not to other reports. In one embodiment, the scrambling sequence is a function of the reporting format. In this embodiment, when the reporting format changes, the scrambling sequence also changes. The scrambling sequence may be used to detect state disconnection, when the base station knows that the terminal uses one reporting format, which situation the terminal knows to use a different reporting format.

11 shows an embodiment of a process 1100 for repeatedly sending reports. The terminal receives an assignment of the control channel (eg, DCCH) used to send the reports (block 1112). The terminal determines the reporting format to use based on the allocation of the control channel (block 1114). For example, the first reporting format may be used for full (eg, full tone) allocation of control channels, and the second reporting format may be used for part (eg, split tone) allocation of control channels. have. The first and second reporting formats may include different numbers of control channel segments in one reporting period and / or different numbers of information bits within each control channel segment. The terminal generates a set of reports for each of the plurality of reporting intervals (block 1116). The terminal sorts the set of reports for each reporting interval according to the reporting format (block 1118). The terminal repeatedly transmits a plurality of sets of reports in a plurality of reporting intervals. (Block 1120)

The reporting format represents a particular sequence of reports sent at a specific location of a control channel frame. The control channel frame is a unit of the control channel used to send a set of reports in accordance with the reporting format. The control channel frame may include a number of control channel segments, for example 40 DCCH segments. The reporting format may include one or more reports in each control channel segment.

The reporting format may include, for example, multiple types of reports on SNR, uplink request, usable transmission power, interference, delay information or combinations thereof, and the like. The reporting format may include any number of reports of each type that may be determined based on the importance of those types of reports. For example, reports for SNR and uplink requests may be sent more often than other types of reports. The reporting format may include reports of different sizes for a given type, multiple reports of a particular type at different locations of the control channel frame, and the like.

The terminal may determine the dictionary to use for each report type from at least one dictionary available for that report. The dictionary for each report type defines the format / structure for each report of that type. The terminal may generate each type of reports according to the dictionaries applicable to that report type. Multiple dictionaries may use for SNR reports, for example, one dictionary for low mobility and another dictionary for high mobility. Multiple dictionaries may also be used in uplink requests for different QoS traffic. Multiple dictionaries may be defined for other report types.

12 shows an embodiment of an apparatus 1200 for repeatedly sending reports. Apparatus 1200 includes means for receiving an assignment of a control channel used to send reports (block 1212), means for determining a reporting format to use based on assignment of a control channel (block 1214), each of a plurality of reporting intervals. Means for generating a set of reports for (block 1216), means for sorting the set of reports for each reporting interval according to the reporting format (block 1218), and repeatedly transmitting the plurality of sets of reports in the plurality of reporting intervals. Means (block 1220).

13 shows an embodiment of a process 1300 for suitably sending reports based on operating conditions. The terminal sends reports to the base station according to the first reporting format (block 1312). The first reporting format may be selected based on the current operating condition or may be a default reporting format. Instructions for using the second reporting format are obtained (block 1314). The base station may select a second reporting format or may send an indication to the terminal with a signal. Optionally, the terminal may select a second reporting format and generate an indication. The terminal then sends the reports according to the second reporting format (block 1316).

For block 1314, the change in operating condition may be sensed by the terminal and / or base station based on, for example, a change in the environment of the terminal, the performance of the terminal, QoS of traffic to the terminal, and the like. The second reporting format may be selected based on the sensed change in the operating condition. For example, a change in mobility of the terminal may be sensed. The second reporting format may then be selected based on the sensed change in mobility. The first reporting format may be appropriate for the first mobility condition (eg, fixed or low speed), and the second reporting format may be suitable for the second mobility condition (eg, high speed). A change in the QoS of the traffic for the terminal may also be detected. The second reporting format may then be selected based on the sensed change in QoS. The first and second reporting format may be designed for different QoS traffic.

Each reporting format may be associated with a specific dictionary. Optionally, dictionaries may be selected regardless of the reporting format. In any case, the terminal determines the appropriate dictionary for using each report in the current reporting format. The terminal generates each type of reports according to the dictionary for that report type.

The change from the first reporting format to the second reporting format may be indicated by a field indicating the reporting format type, for example, as shown in FIG. 10. Changes in the reporting format may also be obtained by signal exchange with the base station.

14 shows an embodiment of an apparatus 1400 for suitably sending reports. Apparatus 1400 sends means according to the first reporting format to the base station (block 1412), means to obtain an indication to use the second reporting format (block 1414) and to send the reports according to the second reporting format. Means (block 1416).

The reporting technique may be used to send reports on the uplink from the terminal to the base station, as described above. Reporting techniques may also be used to send reports on the downlink from a base station to a terminal.

FIG. 15 shows a block diagram of an embodiment of base station 110 and terminal 120 of FIG. 1. At base station 110, transmit (TX) data and signal processor 1510 receives traffic data for the terminal that is serving and signaling. Processor 1510 processes the traffic data, signals, and pilots (eg, such as format, encoding, interleaving, and symbol mapping) and provides output symbols. OFDM modulator 1512 performs OFDM modulation on the output symbols and generates OFDM symbols. Transmitter (TMTR) 1514 adjusts OFDM symbols (eg, converts to analog, filters, amplifies and upconverts) to generate a downlink signal transmitted via antenna 1516.

At terminal 120, antenna 1552 receives downlink signals from base station 110 and other base stations, and provides the received signal to a receiver (RCVR) 1554. Receiver 1554 adjusts and digitizes the received signal and provides samples. An OFDM demodulator (Demod) 1556 performs OFDM demodulation on the samples and provides a frequency domain symbol. Receive (RX) data and signal processor 1558 processes frequency domain symbols (eg, symbol demapping, deinterleaving, and decoding) and provides the decoded data and signal to terminal 120.

On the uplink, controller / processor 1570 generates reports in accordance with the dictionaries and reporting format selected for use. TX data and signal processor 1560 generates output symbols for pilot, traffic data, and signals (eg, reports) sent to base station 110. OFDM modulator 1562 performs OFDM modulation on the output symbol balls and generates OFDM symbols. The transmitter 1564 adjusts the OFDM signal and generates an uplink signal that is transmitted via the antenna 1552.

At base station 110, uplink signals from terminal 120 and other terminals are received by antenna 1516 to recover signal and traffic data transmitted by terminal 120 and other terminals. Coordinated and digitized by 1520, demodulated by OFDM demodulator 1522, and processed by RX data and signal processor 1524.

Controllers / processors 1530 and 1570 direct the operation of various processing units at base station 110 and terminal 120, respectively. The controller / processor 1570 may perform the process 1100 of FIG. 11, the process 1300 of FIG. 13, and / or another process for sending to reports on the uplink. The controller / processor 1530 may receive reports from terminal 120 and other terminals and may schedule transmissions on the uplink and / or downlink based on the reports received from the terminal. The memories 1532 and 1572 store program code and data for each of the base station 110 and the terminal 120.

The reporting techniques described herein may be implemented by various means. For example, these techniques may be implemented in hardware, firmware, software, or a combination thereof. For hardware implementation, a processing unit at a terminal or base station for supporting reporting may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices ( PLDs, field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof. May be

For firmware and / or software implementations, reporting techniques may be implemented with modules (eg, procedures, functions, etc.) that perform the functions described herein. Firmware and / or software codes may be stored in a memory (eg, memory 1532 or 1572 of FIG. 15) and may be executed by a processor (eg, processor 1530 or 1570). The memory may be implemented within the processor or external to the processor.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Those skilled in the art will clearly appreciate various modifications to these embodiments, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments described herein but is to be accorded the widest scope consistent with the principles and novel features as defined by the following claims.

Claims (49)

Generate a set of reports for each of a plurality of reporting intervals, sort the set of reports for each reporting interval according to a reporting format, and repeatedly transmit the plurality of sets of reports in the plurality of reporting intervals, At least one processor; And And a memory coupled to the at least one processor. The method of claim 1, Wherein the reporting format indicates a particular sequence of reports sent at a specific location of a control channel frame. The method of claim 2, The control channel frame includes a plurality of control channel segments, And the reporting format includes at least one report in each of the plurality of control channel segments. The method of claim 1, And the reporting format comprises a plurality of types of reports. The method of claim 4, wherein The plurality of types of the report are for signal to noise ratio (SNR), uplink request, available transmission power, interference, delay information, or a combination thereof. The method of claim 4, wherein And the reporting format includes at least one report for each of the plurality of types, and the number of reports of each type is determined based on the importance of the reports of that type. The method of claim 5, wherein The reports for SNR and uplink request are sent more frequently than other types of reports. The method of claim 1, And the reporting format includes multiple reports of a particular report type at different locations of the control channel frame. The method of claim 1, And the reporting format includes reports of different sizes for at least one type of report. The method of claim 1, And the at least one processor is configured to determine a dictionary for use for a particular type of report among a plurality of dictionaries available for a particular type, and to generate the report of the particular type in accordance with the dictionary. The method of claim 10, And the dictionary defines a format for each report of the particular type. The method of claim 10, The particular type of report is for signal to noise ratio (SNR), wherein the plurality of dictionaries comprises a first dictionary for low mobility and a second dictionary for high mobility. The method of claim 10, The particular type of the report is for an uplink request and the plurality of dictionaries is for traffic of different quality of service (QoS). The method of claim 1, And the at least one processor is configured to receive an assignment of a control channel used to send reports and to determine the reporting format based on the assignment of the control channel. The method of claim 14, The at least one processor is configured to use a first reporting format as the reporting format when a full assignment is received for the control channel, and when a partial assignment is received for the control channel. 2 is configured to use a reporting format as the reporting format. The method of claim 15, The first reporting format includes a first number of control channel segments in one reporting interval. And the second reporting format includes a second number of control channel segments in one reporting interval. The method of claim 15, The first reporting format includes a first number of information bits in each control channel segment, Wherein the second reporting format includes a second number of information bits in each control channel segment. The method of claim 1, And the at least one processor is configured to scramble the set of reports for each reporting interval with a scrambling sequence associated with the reporting format. Generating a set of reports for each of the plurality of reporting intervals; Sorting the set of reports for each reporting interval in accordance with a reporting format; And Repeatedly transmitting a plurality of sets of reports in the plurality of reporting intervals. The method of claim 19, Receiving an assignment of a control channel used to send reports; And Determining the reporting format based on the allocation of the control channel. The method of claim 19, Determining a dictionary to use for a particular type of report from a plurality of dictionaries available for that particular type; And Generating the reports of the particular type in accordance with the dictionary. Means for generating a set of reports for each of the plurality of reporting intervals; Means for sorting the set of reports for each reporting interval in accordance with a reporting format; And Means for repeatedly transmitting a plurality of sets of reports in the plurality of reporting intervals. The method of claim 22, Means for receiving an assignment of a control channel used to send reports; And Means for determining the reporting format based on the allocation of the control channel. The method of claim 22, Means for determining a dictionary for use with a particular type of report from a plurality of dictionaries available for that particular type; and And means for generating the reports of the particular type in accordance with the dictionary. A computer readable medium comprising instructions stored on a computer readable medium, A first set of instructions for generating a set of reports for each of a plurality of reporting intervals; A second instruction set for sorting the set of reports for each reporting interval in accordance with a reporting format; And And a third set of instructions indicative of repetitive transmission of a plurality of sets of reports in the plurality of reporting intervals. At least one processor configured to send reports in accordance with a first reporting format, obtain an indication for using a second reporting format, and send a report in accordance with the second reporting format; And And a memory coupled to the at least one processor. The method of claim 26, Wherein each of the first and second reporting formats represents a particular sequence of reports sent at a particular location of a control channel frame. The method of claim 26, And the at least one processor is configured to use the second reporting format to receive a signal having the indication to use the second reporting format. The method of claim 26, The at least one processor is configured to detect a change in an operating condition, select the second reporting format based on the detected change in the operating condition, and generate the indication to use the second reporting format. , Terminal. The method of claim 29, The operating condition is characterized by the environment of the terminal, the performance of the terminal, the quality of service (QoS) of the traffic for the terminal, or a combination thereof. The method of claim 26, The at least one processor detects a change in mobility of the terminal, selects the second reporting format based on the detected change in mobility of the terminal, and provides the indication to use the second reporting format. Terminal, configured to generate. The method of claim 26, The at least one processor detects a change in the quality of service (QoS) of traffic for the terminal, selects the second reporting format based on the detected change in QoS, and the second reporting format And generate the indication for use. The method of claim 26, The first reporting format is a default reporting format. The method of claim 26, Each of the first and second reporting formats includes a field indicating a reporting format type for a current reporting interval. The method of claim 26, Wherein each of the first and second reporting formats includes a field indicating a reporting format type for a subsequent reporting interval. The method of claim 26, And the at least one processor is configured to exchange signals with a base station to change from the first reporting format to the second reporting format. The method of claim 26, Wherein the first and second reporting formats are associated with first and second dictionaries, respectively, for a particular report type, each dictionary defining a format for each of the particular type of report. The method of claim 26, Wherein the at least one processor is configured to encode information bits for a report to generate code bits and to scramble the code bits or information bits for the report. The method of claim 26, And the at least one processor is configured to scramble a selected one of the reports sent according to the first and second reporting format. The method of claim 26, The at least one processor is configured to use a first scrambling sequence for reports sent according to the first reporting format and to use a second scrambling sequence for reports sent according to the second reporting format. , Terminal. Sending reports according to the first reporting format; Obtaining an indication to use a second reporting format; And Sending reports in accordance with the second reporting format. 42. The method of claim 41 wherein Detecting a change in an operating condition; And Selecting the second reporting format based on the sensed change in the operating condition. 42. The method of claim 41 wherein Detecting a change in mobility of the terminal; And Selecting the second reporting format based on the sensed change in mobility of the terminal. 42. The method of claim 41 wherein Detecting a change in quality of service (QoS) of traffic for the terminal; And Selecting the second reporting format based on the sensed change in quality of service (QoS). Means for sending reports in accordance with the first reporting format; Means for obtaining an indication to use a second reporting format; And Means for sending reports in accordance with the second reporting format. The method of claim 45, Means for detecting a change in operating conditions; And Means for selecting the second reporting format based on the sensed change in the operating condition. The method of claim 45, Means for detecting a change in mobility of the terminal; And Means for selecting the second reporting format based on the sensed change in mobility of the terminal. The method of claim 45, Means for detecting a change in the quality of service (QoS) of traffic for the terminal; And Means for selecting the second reporting format based on the sensed change in the quality of service (QoS). A computer readable medium comprising instructions stored on a computer readable medium, A first set of instructions for generating reports in accordance with a first reporting format; A second instruction set for obtaining an indication to use a second reporting format; And And a third set of instructions for generating reports in accordance with the second reporting format.

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